The chamber first appeared in Relocated: Part Three, where Sarge had Lopez build the chamber for the purpose of testing a new version of the Warthog. The chamber proves quite beneficial at first, allowing the Red Team to test their weapons, such as the EMP cannon, and allow Sarge to relief his stress by constantly "killing" Holo-Grif, an A.I. inside the chamber's programming. The Holo-Chamber can also make other objects, as stated by Lopez in Relocated: Part Four.

In Free Refills, Simmons uses the chamber to speak to a Holo-Sarge and try to improve the EMP warthog, but the real Sarge orders him to stop. After Caboose sneaks into the Red base, he uses the Holo-Chamber to activate the Epsilon unit, which allows Epsilon-Delta to communicate with him in One New Message. In Change of Plans, Carolina and Epsilon use the chamber to show the Reds and Blues images of the Director's secret locations and to explain their plan. However, the group soon have a tense argument, which ends with Epsilon stating the two teams are nothing but problems, nearly destroying the group's relationship as they leave.